Substituted 4-hydroxyalkylamino-1, 8-naphthalic acid imides



Patented Feb. 4, 1947 SUBSTITUTED 4 -HYDROXYALKYLAMINO- 1,8NAPHTHALIC ACID IMIDES Mario Scalera, Somervill Plainfield, N. 3., assig e, and Asa Willard Joyce, nors to American Cyanamid Company, New York, N. Y., a corporation of Maine No Drawing. Application September 5, 1942,

Serial No. 457,518

5 Claims.

This invention relates to certain new 4-amino- 1,8-naphthalimides.

The compounds of the present invention correspond to the following formula:

NHR

in which R is a hydroxyalkyl radical and R is a saturated hydrocarbon radical. The compounds are yellow dyestuffs which have a strong fluorescense under ultraviolet light. The dyestufis may be used for dyeing various plastics and certain of the dyestuffs, particularly those in which R is hydroxyalkyl radical of 2 or 3 carbon atoms and R is a lower alkyl radical having from 1 to 5 carbon atoms, show excellent afiinity to cellulose acetate and may be used in dyeing cellulose parted to plastics and certain synthetic fibers by dyestuffs of the present invention are very brilliant, being golden yellow by transmitted light and greenish yellow by reflected light and fluorescing strongly in the green under ultraviolet light. They are useful for various purposes including objects which must show strong fluorescence for use in blackouts, displays for theatrical performances and the like.

While the present invention is not limited to any particular process of preparing the compounds, a very satisfactory process consists in first reacting a l-halogen naphthalic anhydride with the desired saturated amine to produce the corresponding imide, and then reacting the halogenated imide with the desired alkylolamine.

The reactivity of the anhydride group with amines is much greater than that of the halogen group and therefore if the first step of the process is carried out in an inert diluent, and the amine is present in theoretical amounts, or at least without any considerable excess, the reaction takes place practically exclusively with the anhydride group. The alkylolamine reaction then takes place by heating with the alkylolamine in considerable excess, or by heating with a theoretical amount of alkylolamine in an inert diluent. In the latter case the heating should take place in the presence of a cupriferous catalyst and preferably of a substance capable of uniting with the hydrogen halide set free. When the second step is carried out in the same inert diluent it becomes unnecessary to isolate the halogenated imide.

While either the 4-bromo-naphthalic anhydride or the l-chlcro compound may be used as starting materials, the bromo compound is more reactive and hence in most cases preferable.

The first step of the process is not critical as to temperature because of the much greater reactivity of the anhydride group. In the second step temperatures of 130-l50 C. are suitable when the reaction is carried out with an excess of amine and without diluent and catalyst. If

carried out in an inert diluent such as for example dichlorobenzene, temperatures are preferably 150-180 C. and a cupriferous catalyst and an acid binder are used. The cupriferous catalyst is not critical and the ordinary types of catalysts such as copper powder, cupric chloride, cuprous chloride, cuprous iodide or mixtures of copper powder with iodine may be employed. The acid binding material may be of any suitable type,

alkali metal carbonates and acetates giving excellent results.

The preferred imides are those containing lower alkyl groups, particularly butyl 0r amyl imides. The particular isomeric amine is not important and any of the isomeric primarybutyl 0r amylamines may be used or, if desired, mixtures of isomers may be employed. This is an advantage as mixed isomeric amines are frequently cheaper than pure isomers themselves.

The primary alkylolamine may be any of the ordinary primary alkylol amines. The most valuable products are obtained from p-hydroxyethylamine or B-hydroxypropylamine.

The invention will be described in greater detai1 in conjunction with the following typical examples. The parts are by weight.

Example 1 N-CHzCHzCH2CHs (I30 CIO 55.4 parts 4-bromo-Ls-naphthalic anhydride (M. P. 2l8-19 C.) are introduced into 455 parts o-dichlorobenzene; the mixture is stirred and heated to 135-140 C. 16.0 parts n-butylamine are now added gradually over the course of 2 hours. After heating an hour longer water and excess butylamine are removed by gradually rais- Example 2 NCsHu O CO 100 parts 4-bromo-l,8-naphthalic anhydride (melting point 218-19 C.) are introduced into 260 parts-o-dichlorobenzenes; the charge is stirred, and heated to 13540 G. Then 40 parts commercial amylamine are added gradually during the course of 2 hours, water and excess amyl- A homogeneous deep brownish-yellow mass is formed. 180 parts monochlorobenzene are now introduced and the mixture heated to boiling until solution results. On cooling a mass of yellow crystals separates which is filtered off and washed with water. The yellow 4-ethanolamino- 1,8-naphthalic acid n-butylamide may be recrystallized from monochlorobenzene and melts at l68-169 C. It is readily soluble in alcohol and acetone, sparingly soluble in monochlorobenzene and insoluble in hexane. It is readily dispersed in dilute soap solutions from which it colors Celanese a strong greenish-yellow shade exhibiting an intense fluorescence, especially under the ultra-violet lamp.

' Example 4 NHCHzCHzOH Example 5 Cs u o 00 l l NHCHzCHOHCHs 4-bromo-L8-naphthalic acid amylamide prepared as described in Example 2 is reacted with amine refluxing. After heating for 2-3 hours longer at 135-140" C. the water and excess amylamine are removed by distilling and raising the temperature of the reaction mixture to 160-165 C. On cooling to room temperature there is no separation of the reaction product. To isolate it o-dichloro-benzene isremcved by steaming. A viscous yellow liquid remains which solidifies on cooling. The yield is nearly theoretical. On recrystallization from alcohol the 4-bromo-1,8- naphthalic acid N-amylimide is obtained in pale yellow crystals melting at 73-75 C.

Example 3 N-CHzCHrCHaCH: CO ('30 NHCHzCHaOH 33.2 parts 4-bromo-L8-naphthalic acid n-butylimide and 18.3 parts monoethanol amine are stirred and heated at 135-140" C.

fl-hydrcxypropylamine, the procedure of Example 3 being followed using corresponding weights of the hydroxy propylamine for the monoethanolamine. A yellow dye is obtained which dyes plastics a greenish-yellow shade and fluoresces strongly under ultraviolet light.

Example 6 27.? parts 4-bromo-L8-naphthalic anhydride for 4 hours. acetic acid.

Example 7 N-C u u NHR in which R is an akylol group having less than four carbon atoms and R is a radical of a saturated hydrocarbon of less than seven carbon atoms.

2. New compounds having the following general formula:

NHR

where R is an alkylol group having less than four carbon atoms and n is an integer selected from the group consisting of 2 and 3.

3. A 4-fi-hydroxyethylamine 1,8-naphthalic acid butylimide having the following formula:

N-CaHv NHCHzOHaOH 4. A 4-,3-hydroxyethylan:ine-1,8 naphthalic acid amylimide having the following formula:

N-CsHn i pm NHCHzCHzOH 5. A 4-p-hydroxyethylamine 1,8 naphthalic acid n-butylimide having the following formula:

N-CHnCHzCHzCHs NHCH2CH2OH MARIO SCALERA. ASA WILLARD JOYCE.

REFERENCES. CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,796,011 Eckert Mar. 10, 1931 1,796,012 Eckert Mar. 10, 1931 1,984,110 Bodmer Dec. 11, 1934 2,006,017 Eckert June 25, 1935 1,836,529 Eckert Dec. 15, 1931 1,886,797 Eckert Nov. 8, 1932 1,918,461 Eckert July 18, 1933 2,096,295 Eckert Oct. 19, 1937 

